Mechanisms, application advances and future perspectives of microbial-induced heavy metal precipitation: A review

Heavy metal pollution is insidious, long-term and irreversible, which seriously endangers the environment and human health. Compared with physical and chemical remediation techniques, microbial mineralization technology has been widely studied in the remediation of heavy metal contaminated soil and water due to wide occurrence. This paper mainly reviews the mechanisms, application examples and influencing factors of microbial-induced carbonate precipitation (MICP), microbial-induced phosphate precipitation (MIPP), and microbial-induced sulfide precipitation (MISP). It was found that MICP is more widely studied, but the mineralization products formed by the MIPP process are more stable in the natural environment. Besides, MISP is more suitable for use in anaerobic environments. In addition to various types of bacteria, the biomineralization effects and mechanisms of algae which are more environmentally friendly and fungi which are more abundant and have better tolerance to heavy metals should be intensively studied subsequently. We also summarized the recent research progress of these three mechanisms for biomineralization of heavy metals and radionuclides and analyzed the influencing factors including microbial characteristics, environmental factors, and engineering application processes. Finally, the subsequent research directions that need to be continued in depth for the remediation of heavy metal pollution by microbial mineralization were proposed, so as to promote the large-scale application of microbial mineralization technology in the remediation of heavy metal-contaminated soil and water bodies.